The wreck of a Nazi submarine linked to rumors about the secret smuggling of the Nazi elite to South America at the end of WWII has been discovered off the Danish coast.

The submarine, called U-3523, was recently discovered by the Sea War Museum Jutland over 16 kilometers (10 miles) from the coast of Skagerrak, Denmark's most northern town. This class of submarine, a Type XXI U-boat, was one of Germany's most formidable pieces of naval technology during the war. Unlike most submarines at the time, it was able to operate for long periods submerged underwater at speeds of up to 31.9 kilometers (19.8 miles) per hour.

Multibeam imaging scans of the wreck revealed that submarine was laying on the floor of the sea at a depth around 123 meters (400 feet). Unusually, it was resting with its nose pointed diagonally into the seabed, with its stern remaining some 20 meters (65 feet) above the seafloor.

[...] According to the Sea War Museum Jutland, many have argued the U-3523 was the first real submarine that could have sailed all the way across the Atlantic in one stretch at deep depths.

In the 1970s, when Microsoft and Apple were founded, programming was an art only a limited group of dedicated enthusiasts actually knew how to perform properly. CPUs were rather slow, personal computers had a very limited amount of memory, and monitors were lo-res. To create something decent, a programmer had to fight against actual hardware limitations.

In order to win in this war, programmers had to be both trained and talented in computer science, a science that was at that time mostly about algorithms and data structures.

[...] Most programmers were calling themselves "hackers," even though in the early 1980s this word, according to Steven Levy's book Hackers: Heroes of the Computer Revolution, "had acquired a specific and negative connotation." Since the 1990s, this label has become "a shibboleth that identifies one as a member of the tribe," as linguist Geoff Nunberg pointed out.

What exactly makes a woman? Track and field's world governing body thinks the answer has to do with levels of serum testosterone, at least when it comes to female runners competing in middle-distance races.

The International Association of Athletics Federation announced a new set of rules Thursday that will ban women who naturally produce higher-than-normal levels of testosterone from participating in races ranging from 400 meters to the mile, unless they agree to take medication. Athletes with the condition, called hyperandrogenism, would be eligible to compete at the international level only if they reduced blood testosterone levels through the use of hormonal contraceptives, including birth control pills. The rule will go into effect on Nov. 1.

"Our evidence and data show that testosterone, either naturally produced or artificially inserted into the body, provides significant performance advantages in female athletes," said IAAF President Sebastian Coe in a statement. "The revised rules are not about cheating, no athlete with a [difference of sexual development] has cheated, they are about levelling the playing field to ensure fair and meaningful competition in the sport of athletics where success is determined by talent, dedication and hard work rather than other contributing factors," he added.

The new stipulations are stricter than those established by the IAAF in 2011, which limited women's testosterone levels to 10 nanomoles per liter of blood. The new requirements reduce the limit by half to 5 nanomoles per liter. That is still far above levels in most women, including elite female athletes, whose levels range from 0.12 to 1.79 nanomoles per liter, states a 22-page IAAF document [auto-download PDF] defending the organization's decision. Meanwhile, the normal male range after puberty is much higher, from 7.7 to 29.4 nanomoles.

Previously, the Court of Arbitration for Sport struck down the IAAF's hyperandrogenism regulations in response to a challenge by sprinter Dutee Chand.

As residents of Arizona's eighth congressional district cast ballots in a special election to replace former Rep. Trent Franks (R-AZ) in Congress, roughly 140,000 of them may be unaware they are eligible to vote because they did not receive the ID card the county is required to send them after they register.

According to the Arizona Republic, Maricopa County officials have not sent all voters the cards they can use to cast a ballot under Arizona's voter ID law because of an issue with the company used to print the materials. The paper reports that just 60,000 ID cards have been mailed to people who recently registered or changed their registration, while about 140,000 have not been sent.

[...] Arizona was one of the first states in the country to enact a non-photo voter ID law when a ballot measure was approved by voters[1] in November 2004. Under the law, the state must take steps to ensure that all eligible voters have an acceptable form of ID. According to the secretary of state's office[PDF], "a county recorder must issue a voter ID card to any new registrant or an existing registrant who updates his or her name, address, or political party preference".

But because of an error by the company used to print the ID cards, they have not been mailed out since December.

Although these citizens could provide other forms of ID at the polls, some voters told the Arizona Republic they're concerned that less informed voters may not realize they are registered without the card.

[...] During the presidential primary in March 2016, some Maricopa County voters waited in line for up to five hours to cast a ballot. The chaos led to an investigation by the Department of Justice and numerous lawsuits, including one filed by the Democratic National Committee.

Before the U.S. Supreme Court gutted the Voting Rights Act in 2013, Arizona was required to pre-clear any changes to its voting law with the DOJ.

Millions of electronic door locks fitted to hotel rooms worldwide have been found to be vulnerable to a hack. Researchers say flaws they found in the equipment's software meant they could create "master keys" that opened the rooms without leaving an activity log.

The F-Secure team said it had worked with the locks' maker over the past year to create a fix. But the Swedish manufacturer is playing down the risk to those hotels that have yet to install an update. "Vision Software is a 20-year-old product, which has been compromised after 12 years and thousands of hours of intensive work by two employees at F-Secure," said a spokeswoman for the company, Assa Abloy.

Where do seabirds go when their nesting colony is buried by a volcano? In 2008, the eruption of the Kasatochi volcano in the Aleutian archipelago provided a rare opportunity to track how the island's Crested and Least auklet populations responded when their nesting colony was abruptly destroyed. As a new study from The Auk: Ornithological Advances shows, the birds were surprisingly adaptable, establishing a new colony on freshly created habitat nearby in only four years.

Crested and Least auklets rely on habitat that must be maintained by continual disturbance -- they nest in crevices in talus slopes formed by rock falls, which eventually become unusable when they're filled in with soil and debris. The volcano's 2008 eruption buried all of the suitable nesting habitat for the 100,000 Crested Auklets and 150,000 Least Auklets that had been nesting on Kasatochi.

[...]"The volcanic eruption at Kasatochi in 2008 provided the rare opportunity to document the response of a colonial seabird to the sudden and complete destruction of their nesting habitat. This study capitalized on that opportunity and gives us a glimpse into the ability of these species to disperse to nearby colonies and colonize new habitat," adds the University of New Brunswick's Heather Major, an expert on Aleutian seabirds who was not involved in the study. "This study is therefore important to our understanding of dispersal and habitat selection, and more generally, the ability of these two species to respond to large disturbances at their nesting colonies."

It is a good question, but I was a little surprised to see it as the title of a research paper in a medical journal: "How Happy Is Too Happy?"

Yet there it was in a publication from 2012. The article was grappling with the issue of how we should deal with the possibility of manipulating people's moods and feelings of happiness through brain stimulation. If you have direct access to the reward system and can turn the feeling of euphoria up or down, who decides what the level should be? The doctors or the person whose brain is on the line?

The authors were asking this question because of a patient who wanted to decide the matter for himself: a 33-year-old German man who had been suffering for many years from severe OCD and generalized anxiety syndrome. A few years earlier, his doctors had implanted electrodes in a central part of his brain's reward system—namely, the nucleus accumbens. Electrically stimulating the patient's brain had worked rather well on his symptoms, but now it was time to change the stimulator battery.

Snap today released the next generation of Spectacles, its wearable camera, with new features for taking photos and water resistance. The sunglasses, which have the same striking form as the first-generation model, have been slimmed down and now come in three jewel tones: onyx (black), ruby (red), and sapphire (blue). They're available to order starting today at Spectacles.com for $150 — $20 more than the previous model.

If you've followed the story of Spectacles so far, you know that the first version proved to be a costly misstep for Snap Inc. Although reviewers were generally impressed with their whimsical design, Snap made far more units than the 150,000 or so that it ultimately sold. The company wrote down nearly $40 million in merchandise, and laid off about a dozen people.

Even worse, from the company's perspective, is that people who bought Spectacles didn't use them for very long. According to Business Insider, less than half of users continued to use Spectacles a month after buying them. They were presented as the future of communication, but the first iteration of Spectacles felt more like a toy — a relatively cheap novelty that people used a handful of times before stuffing into a drawer.

Magnetic resonance imaging, or MRI, is a widely used medical tool for taking pictures of the insides of our body. One way to make MRI scans easier to read is through the use of contrast agents -- magnetic dyes injected into the blood or given orally to patients that then travel to organs and tissues, making them easier to see. Recently, researchers have begun to develop next-generation contrast agents, such as magnetic nanoparticles, that can be directed specifically to sites of interest, such as tumors.

But there remains a problem with many of these agents: they are sometimes difficult to distinguish from our bodies' tissues, which give off their own MRI signals. For example, a researcher reading an MRI scan may not know with certainty if a dark patch near a tumor represents a contrast agent bound to the tumor, or is an unrelated signal from surrounding tissue.

Caltech's Mikhail Shapiro, assistant professor of chemical engineering, thinks he has a solution. He and his team are working on "erasable" contrast agents that would have the ability to blink off, on command, thereby revealing their location in the body.

"We're developing MRI contrast agents that can be erased with ultrasound, allowing you to turn them off," says Shapiro, who is also a Schlinger Scholar and Heritage Medical Research Institute Investigator. "It's the same principle behind blinking bicycle lights. Having the lights turn on and off makes them easier to see, only in our case we just blink off the contrast agent once."

The new research was published in the February 26 advanced issue of Nature Materials, and is on the cover of the May print edition out this month. The lead author is George Lu, a postdoctoral scholar in Shapiro's lab.

For decades, the Urabá region, just across the border in [geologist Camilo] Montes's home country, was occupied by the Revolutionary Armed Forces of Colombia (FARC), a leftist guerrilla group that had waged war on the Colombian state since 1964. "Those who went in never came out," Montes says. That all changed with a stroke of a pen on 26 September 2016, when Colombian President Juan Manuel Santos signed a peace deal with the FARC. Guerrilla fighters shuttered their jungle camps and handed over their weapons.

Now, Montes and other Colombian scientists are rushing in, exploring the geology of their country, its wealth of species, and how its ecosystems are coping with stresses such as deforestation and climate change. Those forays are risky: Vast areas haven't yet been cleared of land mines (see sidebar), and drug traffickers, paramilitary groups, and non-FARC armed insurgents plague the countryside. But the researchers are seduced by the prospect of prying scientific secrets from huge swaths of land that are no longer off-limits. Urabá's geology, Montes says, "is all a blank slate."

[...] Now that researchers are more free to explore, they are finding that the long conflict had an ecological upside: suppressing development in guerrilla-held territory. FARC fighters deforested some areas to plant coca, but their camps were well hidden and had a light environmental footprint. The violence also deterred farmers and ranchers from encroaching on the wilderness. [...] But the once-occupied ecosystems won't remain pristine for much longer, Link says. "These areas haven't just opened up for scientists," he says. "They've opened up for the whole machinery of development." Deforestation is picking up nationwide, including in Colombia's Amazon region, as farmers clear forest for pastures and crops. In 2016, the last year for which statistics are available, deforestation in Colombia jumped 44%. "The country is experiencing more environmental deterioration than ever before," Link says.

After 6 long years, GIMP has finally released version 2.10 using the Generic Graphics Library (GEGL) for high bit depth processing. This release comes with a brand new interface, better integrated color management, a new unified transform tool for scaling, rotating, and correcting perspective, and many other improvements and tools.

High bit depth support allows processing images with up to 32-bit per color channel precision and open/export PSD, TIFF, PNG, EXR, and RGBE files in their native fidelity. Additionally, FITS images can be opened with up to 64-bit per channel precision.

Multi-threading allows making use of multiple cores for processing. Not all features in GIMP make use of that, it's something we intend to work on further. A point of interest is that multi-threading happens through GEGL processing, but also in core GIMP itself, for instance to separate painting from display code.

GPU-side processing is still optional, but available for systems with stable OpenCL drivers.

[...] Some of the new GEGL-based filters are specifically targeted at photographers: Exposure, Shadows-Highlights, High-pass, Wavelet Decompose, Panorama Projection and others will be an important addition to your toolbox.

The WebP lossy image format, which is now supported by GIMP, was updated by Google to v1.0.0 on April 2.

Google is the latest company to ditch the pistol with a new emoji update for Android users. The switch to a bright orange and yellow water gun, rolling out now, mimics changes made by Apple, WhatsApp, Twitter, and Samsung over the last few years. That leaves Microsoft as the only major platform with the realistic handgun emoji. True, Facebook still uses it, but a spokesperson for the company confirmed to Emojipedia that it would also be replacing its gun emoji with a toy water gun. The Verge has reached out to Microsoft for comment.

[...] Ironically, Microsoft initially displayed the gun emoji as a toy, but changed it to a revolver in 2016 as part of its emoji redesign project. With Google's (and Facebook's) latest move, Microsoft's gun emoji puts it at philosophical odds with the other giant tech companies based in the US where gun violence is a major concern. As we previously noted, in 2016 Apple successfully pushed to remove the rifle icon from the standardized collection of emoji.